**7. Angioplasty technique used**

New foci (NF) of ischemia were defined as the presence of a hypersignal (restriction) in diffusion after CAS that was not present in the same sequence before CAS. These foci were

The opposite of a recent infarction caused by DWI after CAS is an old infarction that is present in the T2W sequencing of the MRI before CAS. Chronic cerebral infarction is the end result of prolonged ischemia. Areas of hypersignal in the cerebral parenchyma in the T2 sequence with areas corresponding to the variable signal in T1 (with the tendency to be isointense compared with the fluid in T1 and T2) without restriction in DWI and with no enhancement after paramagnetic contrast were considered old infarctions ("T2W infarction"). Other diseases that may have a signal aspect similar to that of old infarctions (for example: porencephalic cysts, arachnoid cysts, low-grade astrocytoma) were excluded from the count because of their topographic characteristics, their appearance on the edge of the lesion, or their appearance on the surrounding tissue or because they showed a signal that differed from that of the fluid in

The MRI images were analyzed by the consensus of two experienced neuroradiologists using the eFilm® software without access to the clinical data or angiography and CAS data. If there were discrepancies between the two neuroradiologists' findings, the studies were analyzed by

The NF were correlated with age, gender, side of carotid artery treated, presence of previous symptoms related to carotid stenosis, risk factors for atherosclerosis and ICVA (diabetes mellitus, systemic arterial hypertension, hypercholesterolemia, ischemic coronary artery disease, arrhythmia, ischemic peripheral vascular disease, transient ischemic attack [TIA], and ischemic cerebrovascular accident [ICVA]), percentage of carotid stenosis, presence of ulcers in the atheromatous plaque, previous infarction noted on the MRI, number of catheters used, number of arteries on which angiographies were performed, contralateral carotid occlusion, endovascular access technique used to reach the common carotid artery on the side of the angioplasty, type of filter, type of stent, volume of contrast used in the CAS and angiography, fluoroscopy time spent during the procedure, and the localization, number, and diameter of these NF. These parameters were also correlated between patients with only one NF and those

The localization (laterality) of the encephalic NF was defined as ipsilateral if it coincided with the area supplied by the carotid artery undergoing angioplasty. The localization of the NF was defined as contralateral if the cerebral area did not coincide with the side of the CAS, meaning the area was nourished by the carotid artery contralateral to the angioplasty or the area located on the posterior fossa. In cases when it was impossible to determine laterality, the patient was excluded from the analysis, which occurred with two patients. Patients 16 and 27 showed stenosis in the carotid artery (left) and contralateral occlusion (right), with NF identified in the area supplied by the right carotid artery. Under this condition, the flow to the carotid area can use the anastomotic Willis polygon or openings in other collateral pathways can be determined (for example: flow through the vasa vasorum or retrograde flow through the ophthalmic artery). Thus, with NF in the area of the occluded artery, it is not possible to say with certainty whether the embolism originated directly in the CAS or migrated through the anastomosis of areas that revascularized the cerebral territory of the occluded carotid artery. Because of the

considered recent, additional infarcts compared with the first MRI.

the other sequences in the MRI study.

158 Carotid Artery Disease - From Bench to Bedside and Beyond

a third observer to reach a consensus.

with multiple NFs.

The patients were divided into two groups: "brief" angiography and "complete" angiography. An angiographic exam before CAS is conventionally called a brief angiography when the exam only includes an angiography of the carotid artery that is a candidate for treatment. A complete angiography includes the study of other cervical arteries or the aortic arch.

Antiplatelet therapy was standardized, and all patients received 75 mg clopidogrel and 100 mg acetylsalicylic acid orally on a daily basis, beginning at least five days before the procedure.

In the preparation of the materials, all of the introducers, catheters, and sheaths were pre‐ washed with physiologic saline flow and subsequently packed in a sterile container with physiologic serum and heparin before arterial puncture.

Under local anesthesia and light sedation from the anesthesiologist, arterial puncture was performed and the valved introducer was deployed in the common femoral artery, which was fixed to the skin with a wire suture for safety. If there was significant tortuosity of the iliac and femoral vessels, long introducers were sufficient to help stabilize the catheter and the catheter guide in the common carotid arteries.

A bolus injection of 10,000 units of heparin was administered intravenously after the valved introducer was installed. An atropine solution was prepared before the angioplasty and stored until the stent's release. Intermittent verbal communication was maintained with the patient during the procedure by the doctors performing the CAS, as in the eventual clinical tests.

In all cases, the angiography of the carotid artery undergoing CAS was initially performed with a 5 Fr angiographic catheter to confirm the stenosis shown with other methods. At this point in the procedure, angiographies of the cerebral vessels nourished by the carotid artery were performed, and they were repeated at the end of the CAS to observe any possible arterial occlusion. In all cases, a noniconic contrast with low osmolarity was used.

After the stent was released, 0.5 mg of atropine was administered intravenously. After tachycardia was observed, a catheter balloon was inserted and inflated inside the stent. The angioplasty balloon had the function of shaping the stent smoothly. The same balloon size was used for all of the procedures: 6 mm in diameter and 20 mm in length (Gazele®, Boston Scietific/ Target and Amiia®, Cordis). In this study, after the balloon was deflated, an immediate-control cervical angioplasty was conducted with a smooth manual injection of the contrast medium

Cerebral Protection in Carotid Angioplasty – Is There a Need? Advantages and Disadvantages of...

http://dx.doi.org/10.5772/57154

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Once control via cervical DSA at the end of the CAS was considered satisfactory (residual stenosis at a maximum of 30%), the filter was collected. Later, after the removal of the filter and the last stage of CAS, carotid angiographies for intracranial vascularization were per‐ formed in anteroposterior (AP) and profile to show that the artery subjected to CAS remained patent. Additionally, the intracranial vessels were thoroughly studied and compared with the preangioplasty angiograms to detect any macroemboli. The catheter guide was removed at the end of the CAS, leaving only the arterial introducer in the inguinal region. Heparin was not antagonized. After the CAS, the cases were monitored in the intermediate intensive care unit for 12 to 24 hours with attention to the patient's neurological state and especially his/her

All of the procedures were performed by an experienced neuroradiologist (with over 20 years of specialty experience) with the help of one or two residents. No patient showed any neuro‐ logical or other symptoms after the CAS. The follow-up for clinical observations was the in-

The data were analyzed using several methods and logistic regression analysis. All cases were evaluated using SPSS (Version 15.0). A p-value <0.005 was considered statistically significant.

**Figure 3.** Patient number 2, 70 years old, male with diabetes, hypertension and coronary ischemia, displayed transient ischemic attack. . DWI exam after CAS (not shown) did not reveal micrusemboli. Angiography showed stenosis of 70% (A) in the left carotid artery with additional imaging (ulcer). EPI® open carotid filter (arrow) and Wallstent (7 x 40 mm)

to avoid disturbing the filter and possibly mobilizing any waste that it retained.

blood pressure.

hospital period of four days.

self-expandable stent (B). Control angiography after CAS (C)

In all cases (n=36), an 8 Fr-caliber guide catheter was introduced into the common femoral artery inside the valved introducer, and the distal extremity was positioned in the common carotid artery undergoing CAS a few centimeters below the atherosclerotic plaque.

The possible methods for positioning the catheter guide safely in the common carotid artery, close to the bulb, were defined as access techniques. The endovascular techniques for accessing the carotid artery to be treated included direct access (DA), an exchange with the guide wire in the external carotid artery (ECA), exchange with the guide wire in the common carotid artery (ECC), and triaxial access (TRI). For the direct access technique (DA), the catheter guide was introduced into the common carotid artery by sliding it over a guide wire (0.035 inches) that had previously been placed in the artery.

The technique involving exchange with the guide in the external carotid artery (EEC) was as follows: the tip of the guide wire (0.035 inches) was positioned in the external carotid artery using a diagnostic catheter with a 5-Fr caliber (figure 3). It remained safely in this position without colliding with the atheromatous plaque, providing a means for the catheter guide to advance over the guide until it reached the common carotid artery. The ECC technique was defined as when the guide was positioned in the common carotid artery, rather than the external carotid artery, with the help of a catheter guide contained within a diagnostic catheter. At this point, the catheter was removed, and the catheter guide reached the common carotid artery by going over the guide. The TRI technique involved using a guide catheter with a diagnostic catheter inside (the designs and materials varied for each case) and a guide (0.035 inches) placed inside the diagnostic catheter. The catheter was free to attempt several maneu‐ vers before the catheter guide penetrated the carotid artery for the angioplasty.

After positioning the catheter guide in the common carotid artery, one of the closed filter cerebral protection systems can be extended beyond the stenosis by positioning it a few centimeters above the stenosis close to the base of the skull, preferably in a rectilinear segment open in this topography. We also observed whether the filter was adjusted to the size of the artery to avoid dislocating the filter system during the subsequent maneuvers.

"Rapid exchange" filter systems were used, which consisted of a 0.014-inch microguide with a polyurethane membrane filter with 100 to 140 µm pores (100 µm in AngioGuard® filters [Cordis], 110 µm in EPI FilterWire EPI/EZ® filters [Boston Scientific/Target], and 140 µm in EmboShield® filters [Abbott]).

All of the patients were scheduled for the primary technique (without prior dilation of the stenosis via a balloon) using a stent with an appropriate diameter (7 to 8 mm) for each case and sufficient length to cover the bulb and the entire atherosclerotic plaque distally and inferiorly (at least 1 cm).

Self-expandable stents (Carotid Wallstent®, Boston Scientific/Target; Precise®, Cordis; and Protégé®, ev3) designed for carotid use in a 0.014-inch guide system were used. Only the straight version of the Protégé® stent was used in our study.

After the stent was released, 0.5 mg of atropine was administered intravenously. After tachycardia was observed, a catheter balloon was inserted and inflated inside the stent. The angioplasty balloon had the function of shaping the stent smoothly. The same balloon size was used for all of the procedures: 6 mm in diameter and 20 mm in length (Gazele®, Boston Scietific/ Target and Amiia®, Cordis). In this study, after the balloon was deflated, an immediate-control cervical angioplasty was conducted with a smooth manual injection of the contrast medium to avoid disturbing the filter and possibly mobilizing any waste that it retained.

were performed, and they were repeated at the end of the CAS to observe any possible arterial

In all cases (n=36), an 8 Fr-caliber guide catheter was introduced into the common femoral artery inside the valved introducer, and the distal extremity was positioned in the common

The possible methods for positioning the catheter guide safely in the common carotid artery, close to the bulb, were defined as access techniques. The endovascular techniques for accessing the carotid artery to be treated included direct access (DA), an exchange with the guide wire in the external carotid artery (ECA), exchange with the guide wire in the common carotid artery (ECC), and triaxial access (TRI). For the direct access technique (DA), the catheter guide was introduced into the common carotid artery by sliding it over a guide wire (0.035 inches) that

The technique involving exchange with the guide in the external carotid artery (EEC) was as follows: the tip of the guide wire (0.035 inches) was positioned in the external carotid artery using a diagnostic catheter with a 5-Fr caliber (figure 3). It remained safely in this position without colliding with the atheromatous plaque, providing a means for the catheter guide to advance over the guide until it reached the common carotid artery. The ECC technique was defined as when the guide was positioned in the common carotid artery, rather than the external carotid artery, with the help of a catheter guide contained within a diagnostic catheter. At this point, the catheter was removed, and the catheter guide reached the common carotid artery by going over the guide. The TRI technique involved using a guide catheter with a diagnostic catheter inside (the designs and materials varied for each case) and a guide (0.035 inches) placed inside the diagnostic catheter. The catheter was free to attempt several maneu‐

After positioning the catheter guide in the common carotid artery, one of the closed filter cerebral protection systems can be extended beyond the stenosis by positioning it a few centimeters above the stenosis close to the base of the skull, preferably in a rectilinear segment open in this topography. We also observed whether the filter was adjusted to the size of the

"Rapid exchange" filter systems were used, which consisted of a 0.014-inch microguide with a polyurethane membrane filter with 100 to 140 µm pores (100 µm in AngioGuard® filters [Cordis], 110 µm in EPI FilterWire EPI/EZ® filters [Boston Scientific/Target], and 140 µm in

All of the patients were scheduled for the primary technique (without prior dilation of the stenosis via a balloon) using a stent with an appropriate diameter (7 to 8 mm) for each case and sufficient length to cover the bulb and the entire atherosclerotic plaque distally and

Self-expandable stents (Carotid Wallstent®, Boston Scientific/Target; Precise®, Cordis; and Protégé®, ev3) designed for carotid use in a 0.014-inch guide system were used. Only the

vers before the catheter guide penetrated the carotid artery for the angioplasty.

artery to avoid dislocating the filter system during the subsequent maneuvers.

straight version of the Protégé® stent was used in our study.

carotid artery undergoing CAS a few centimeters below the atherosclerotic plaque.

occlusion. In all cases, a noniconic contrast with low osmolarity was used.

had previously been placed in the artery.

160 Carotid Artery Disease - From Bench to Bedside and Beyond

EmboShield® filters [Abbott]).

inferiorly (at least 1 cm).

Once control via cervical DSA at the end of the CAS was considered satisfactory (residual stenosis at a maximum of 30%), the filter was collected. Later, after the removal of the filter and the last stage of CAS, carotid angiographies for intracranial vascularization were per‐ formed in anteroposterior (AP) and profile to show that the artery subjected to CAS remained patent. Additionally, the intracranial vessels were thoroughly studied and compared with the preangioplasty angiograms to detect any macroemboli. The catheter guide was removed at the end of the CAS, leaving only the arterial introducer in the inguinal region. Heparin was not antagonized. After the CAS, the cases were monitored in the intermediate intensive care unit for 12 to 24 hours with attention to the patient's neurological state and especially his/her blood pressure.

All of the procedures were performed by an experienced neuroradiologist (with over 20 years of specialty experience) with the help of one or two residents. No patient showed any neuro‐ logical or other symptoms after the CAS. The follow-up for clinical observations was the inhospital period of four days.

The data were analyzed using several methods and logistic regression analysis. All cases were evaluated using SPSS (Version 15.0). A p-value <0.005 was considered statistically significant.

**Figure 3.** Patient number 2, 70 years old, male with diabetes, hypertension and coronary ischemia, displayed transient ischemic attack. . DWI exam after CAS (not shown) did not reveal micrusemboli. Angiography showed stenosis of 70% (A) in the left carotid artery with additional imaging (ulcer). EPI® open carotid filter (arrow) and Wallstent (7 x 40 mm) self-expandable stent (B). Control angiography after CAS (C)
